I have just released a small add on for blender: http://blenderartists.org/forum/showthread.php?317584-Alpha-Selection-2-Bill-of-Materials&p=2514432
[strike]Pay attention it’s in very eary alpha beta stage (<48 hours of age)![/strike]
WARNING: BELOW MAY BE OPINION, DISCUSSION OR OUTDATED.
You know I’m overly fond of blender. Asche über mein Haupt dafür!. Many people say it’s impossible to learn. I say, it’s just a question of getting an idea of what blender is capable of and HOW you can make blender all this magic (by tutorials and experience). Then suddenly everything makes sense. If you don’t know any further, just use spacebar and look for the function you just forget where it is hidden in the GUI. And don’t forget SHIFT +A adds objects, then select the one to edit and press TAB - here you are, now with right mouse button you can move the vertices … or use G for translate/move by a certain amount, S for scaling, R for rotating, E for extruding vertices/edges/faces …
What do you think makes sketchup so much better than blender for DIY-Engineering? Sketchup is used more often, even OpenSourceEcology US seems to be fixed on Arduino and Sketchup. Even though Arduino is 8 bit and AVR, i.e. completely dependent on one company (ATMEL), and Sketchup is not open source, is it? (btw blender 2.67+ has 3D print tools too and can export to slic3r or other postprocessing tools for 3D printing …)
MSP430 looks more promising to me. Or what about Beagle Bone Black for 48$? It’s cheaper than Arduino … much cheaper - and still open source. (while the Raspberry PI processor is not open source unfortunately!)
And sketchup, well … why reinventing the wheel, blender can do all this and A LOT more. Only learn one tool and get a hundred goodies for free (e.g. 3D animation of created models, RobotOS integration or robotic simulation http://wiki.blender.org/index.php/Community:Science/Robotics, …).